Bug 1217

Summary: No way to configure Muxed_TMS dispatcher table size and other ideas to reduce size
Product: TAO Reporter: Ossama Othman <ossama.othman>
Component: ORBAssignee: DOC Center Support List (internal) <tao-support>
Status: NEW ---    
Severity: normal    
Priority: P3    
Version: 1.2.3   
Hardware: All   
OS: All   

Description Ossama Othman 2002-06-06 15:52:47 CDT 
The size of the dispatcher table in the TAO_Muxed_TMS class currently cannot 
be configured at ORB initialization time.  This prevents more than 1024 (i.e. 
ACE_DEFAULT_MAP_SIZE) invocations to be simultaneously pending when using the 
MUXED transport muxing strategy.

In practice, this may not be problem since it is unlikely that an application 
will ever have more than 1024 pending invocations.  However, it does 
unnecessarily increase the memory requirements of applications that will never 
have 1024 pending invocations in a MUXED transport muxing strategy 
configuration.
Comment 1 Ossama Othman 2002-06-06 15:53:40 CDT 
Corrected spelling in subject.
Comment 2 Nanbor Wang 2002-06-17 13:54:10 CDT 
Assigning the bug to me
Comment 3 Nanbor Wang 2002-06-17 13:56:21 CDT 
Accepting the bug
Comment 4 Nanbor Wang 2002-12-12 14:58:26 CST 
Changed the summary to add more information on the nature of the bug report. 

There were some ideas floated by Carlos and me thinks they are something to 
think seriously about. Instead of using a Hash_Map in the Muxed_TMS strategy, 
we could use a circular array. We could start of with size 16. Once we run out 
of it we could duplicate at that point. What are the advantages

1. Circular buffer that can be indexed removes the need for forward and 
reverse pointers and that saves us 8 bytes

2. Starting at 16 elements in size cuts down the size of the Transport object 
which in turn encapsulates a connection a lot.

Some practical issues that Carlos pointed out:

----------------------------------------------------------------
Start with a small array (16 entries or so), to create a
request id find the first element "unused" in the array.  If you do
not find any duplicate the size of the array.  Only gotcha I can think
of:  if a request times out you cannot clear the array element, you
need to mark it "timed out" until the reply really arrives.  You could
end up with a lot of timed out requests taking up space.  Using a
circular buffer would solve that, but it has other problems (for
example, it is significantly more complex, though it can be unit
tested!)
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Comment 5 Johnny Willemsen 2007-09-20 03:08:59 CDT 
to pool